The last time I wrote about using Vim to write Clojure, I had just started using it professionally. Now I’m at my second Clojure job and I am still enjoying the its power, combined with the speed of Vim. However, in contrast to the last update, which was incremental to my first post, quite a few things about my setup have changed in the past few years.

Old Faithful

First off, let’s start with the plugins that havent changed.

My config for all of these hasn’t changed. There have been a handful of small updates, but for the most part these plugins are rock solid and reliable.

One thing I will say is that I really enjoy structural editing with the two SExp plugins above. Despite Clojure being a lisp, I can count on one hand the number of times I’ve somehow gotten my parentheses unbalanced. I highly recommend taking the time to learn structural editing. I remember looking at some of the more odd manipulation names (like splice and raise) and thinking I would never use them, but that hasn’t borne out. They come up quite regularly, and I also use the reordering mappings quite a bit. I have never tried parinfer, mostly because I’ve seen people get frustrated at it too often.

I also remain a voracious code folder. I think this throws some people off, but I find it valuable to hide what I am not looking at.

REPL Connection

For quite a while, I was a happy user of Fireplace, but a few years ago I started looking at some of the other Vim plugins that were available1. I settled on Conjure after briefly trying them all out. Each evaluation is its own buffer in Fireplace, and I added some mappings to call them up for reference. Conjure takes another tactic by putting the output from all evaluations into a shared buffer. Early on, this took some getting used to, but I have grown to prefer it this way. Having a common buffer makes it quite easy to reference and compare data together, and has had some surprising uses, such as editing down a portion as a report for others.

I remember when Conjure first started off as a Clojure-based Neovim plugin, with the associated wait time for start up and the occasional orphaned JDK process. I tend to run my Vim session for a while, so this wasn’t a major annoyance, but I am tremendously grateful that it was rewritten into a Fennel/Lua plugin. It loads quite fast and is useful immediately. I also really appreciate the attention that its author Oliver Caldwell has given it over the years and that he continues to innovate with it.

Here are the bindings that I use the most:

  • ,er - Evaluate the root form from where my cursor is. This obviates the need to more my cursor to the top of the form to evaulate with ,ee, and the fewer keystrokes between ESC and evaluation, the better. This even works properly in (comment ...) forms, thanks to the conjure-efroot plugin.
  • ,ew - Evaluate the word under my cursor. This is particularly useful for global defines or vars defined in fiddle code to check their value.
  • ,em[mark] - This is one of Conjure’s coolest features. I can put a mark, such as a, somewhere in my file and evaulate it from wherever my cursor is by hitting ,ema. This is particularly useful for when I’m editing multiple functions and I have a Rich Comment with one or more calls to those functions. I can then load the function definition and run it by hitting ,er followed by ,ema, all without moving my cursor at all. Capital letter marks can be evaluated from other files, and I use this to allow ,emC to call Portal’s clear function to reset its viewport data from anywhere I am working.
  • ,lr - This resets the Conjure log buffer, ready for a fresh set of evaluations.

Fast Linting

Clj-kondo is a linter that has definitely taken over the Clojure community in the past few years. It offers quite a few good suggestions and even has some disabled-by-default rules that can be helpful. I originally used Syntastic to integrate Clj-kondo (like Joker before it), but disliked the pause it took on each file write. I switched over to ALE a couple years ago and haven’t looked back. It runs Clj-kondo in the background and adds its suggestions when finished, allowing me to move on.

For the most part, I leave the ALE configuration stock. I did disable checking in the Conjure buffer, and I added a couple of vim-unimpaired compatible mappings to go between warnings in the file.

" Async Lint Engine config
let g:ale_linters = {'clojure': ['clj-kondo']}
let g:ale_pattern_options = {'conjure-log.*.cljc': {'ale_enabled': 0}}
" Easy navigation between errors
map [w <Plug>(ale_previous_wrap)
map ]w <Plug>(ale_next_wrap)

LSP with clojure-lsp

The Language Server Protocol movement has been quite a revelation for developer tooling. Decoupling the editor from language-specific tooling allows the latter to move at its own pace and benefit all editors. The clojure-lsp project has grown quite a bit and provides all the features and more that I would expect in a sophisticated IDE. Integrating it has impacted my Clojure development workflow as much or more than my switch to Conjure.

Here are the bindings that I use the most:

  • gd (and gD when I want a split) - Jump to definition. This greatly eases opening up related files and I find I can get a faster understanding of a call tree because I can jump as quickly as Clojure would.
  • ,ci and ,co - Incoming and outgoing calls. This pops up a list of the callers or callees of the current function. Again, this greatly enhances my exploration and understanding.
  • ,cr - Rename identifier. I often will pick a bad-but-good-enough name when quickly writing/designing code and this allows me to go back and refine the names. It even works across files.
  • ,c - Bring up code actions for the code my cursor is on. This is how I access most of the occasionally useful actions, like “clean namespace” and “sort map keys.”

One of the coolest features that I only need from time to time is moving pairs up and down. vim-sexp-mappings-for-regular-people has mappings for moving the current element or form backward and forward, and I always wanted to be able to do the same for pairs, such as let bindings and map key/value pairs. Clojure-lsp calls this drag forward/backward, and I mapped that to <p and >p. Now I can move pairs around and I laugh at the magic every time I do.

Future

A lot has changed since I last wrote about Clojure and Neovim, and I haven’t even caught up with most of the cool new things out there. Here are a few that I’m hoping to try out soon.

Fennel/Lua Neovim config

It’s now possible to completely configure Neovim with Lua, and since Fennel compiles to Lua, there are a few brave souls who have converted almost their entire config into lisp! Here are a few of them:

  • Conjure’s creator Oliver Caldwell’s config, also helpfully extracted for use by others as magic-kit
  • Rafael Delboni’s config
  • Practicalli’s config

This is very appealing to me as these configs are well organized and easy to follow and extend.

Native Neovim LSP

Neovim itself has its own LSP server now. I currently integrate with clojure-lsp via the coc.nvim plugin, and its served me well. There was some recent instability that caused me to pin to an older version, but now it is back to stable again. I am curious how the native LSP integration behaves and would like to try it out.

Other Neovim plugins

There are quite a few new plugins out there that are re-imaginings of older plugins. I’m wary of changing too much at once, but over time I will start trying some of them out.

Further reading

All of my configuration is in my dotfiles repo2.

That’s all I have for now.

Enjoy.

  1. How cool is it that we have no fewer than 3 (!!) different ways for Vim to reach out to Clojure. So awesome! ↩︎

  2. I originally started versioning my dotfiles to enable keeping them consistent across different servers. For this post, the history in there was helpful in remembering when I switched between plugins. ↩︎